(also called a "grade IV astrocytoma", "GBM", or "malignant astrocytoma")
Definition: Astrocytomas are tumors that arise from astrocytes, cells in the brain that support and insulate nerve cells. Glioblastoma multiforme tumors (GBM’s) are classified as grade IV by the World Health Organization. They are a relatively common type of primary brain tumor.
Symptoms: The most common initial symptoms of a GBM are due to the fast growth of the tumor causing increased intracranial pressure. These symptoms are severe headaches, seizures, nausea and vomiting, and changes in behavior.
Evaluation: GBM’s are evaluated with MRI scans.
- Surgery: Surgery is recommended to obtain a sample of tissue to confirm the diagnosis, to decrease pressure on the brain, and to reduce the size of tumor to be treated. It is impossible to surgically remove all of the tumor since it mixes with normal brain tissue. A biopsy may be all that is possible if the tumor is located in a critical part of the brain, such as the brainstem, where removal may cause serious neurological problems.
- Radiation: Focal radiation therapy is usually recommended and started two to four weeks after surgery.
- Chemotherapy: Chemotherapy is often started at the same time as radiation as it may sensitize the tumor to radiation. Chemotherapy is usually continued after radiation therapy is completed.
Follow-up: Long-term close follow-up with regular MRI scans is recommended to watch for tumor growth or problems requiring further treatment.